England fast bowler Stephen Harmison is to undergo surgery for a "non-serious hernia" operation, the England and Wales Cricket Board (ECB) announced Tuesday.

However, an ECB spokesman said the timing of the operation had still to be decided and stressed Harmison's ability to bowl was not being affected.

Harmison took the field Tuesday for the last day of the fourth and final Test against the West Indies at his Durham home ground here at the Riverside.

The spokesman said a decision on his availability for Durham's one-day Friends Provident Trophy semi-final against Essex here Wednesday would be made at the end of the Test match.

"Stephen Harmison has a non-series hernia that will require surgery at some stage. It is not currently affecting his bowling and the timing of surgery will be decided by the ECB medical team," the spokesman said.

Harmison, 28, retired from one-day international cricket during England's Ashes tour of Australia and so wouldn't have been available in any event for the two upcoming Twenty20 matches and three one-dayers against the West Indies.

England's first Test against India starts at Lord's on July 19.

Given the average recovery period from hernia surgery is six weeks, this suggests Harmison would have to have an operation as soon as possible to maximise his chances of being available for the whole of the three-Test series.